Or society support mechanisms - many ppl in say Scandinavia use the two or more years of high unemployment benefits to start a business risk-free. Actually in Norway, to stimulate entrepreneurship, they would pay those benefits for the 1st six month of new company operation (to the owner).
I don't think this is true - all the traditional "low risk" professions have this ability: doctors, dentists, lawyers, investment bankers and fund managers. $300k+ is not unusual for a mid-level person in these industries. Senior people in these industries will hit $1m+ pretty easily without having taken on any significant personal risk. A lawyer 3-4 years out from law school in a large firm is going to be sitting on $200k+ already.
This is the OP.
2. Taking a bad important medical decision will have bad financial consequences - lower reputation, not so good references, patient complains leading to big losses of time - lower income in the future. Also there's stuff like which team do you join, what new technical skills do you get, which part of the world you work in. You take a lot of risk, you can expect higher rewards on success.
One knows all the risks involved in his job, and few in other's jobs.
But to break the 99th percentile - I think that was $342K/year for 99.5th percentile of single filers - you need to take on some risk. Like forgoing your income for a few years to found a company. Or taking on a lower salary and the risk that you'll be laid off in a year and getting a job at a startup. Or putting up your own money to invest in one. Or taking on high-visibility, high-impact projects that may fail - often at the cost of your regular duties - within your day job.
For people whose whole life has been a steady upwards progression, risk is scary. It often looks impossible. And so they're stuck at a point in life where they know people who have vastly more money than them, but they don't understand how or are unwilling to achieve that.